Inventor Part Modeling
Sketching and Constraints
A robust part starts with a fully constrained sketch. Understand geometric constraints (coincident, collinear, parallel, perpendicular, tangent, concentric, equal) and dimensional constraints. The trap: over-constraining or leaving under-constrained geometry. Use the status bar to confirm the sketch is fully constrained before extruding.
Feature Creation
Primary features: extrude, revolve, sweep, loft, hole, thread, rib, emboss. Secondary features: fillet, chamfer, shell, draft, pattern, mirror. Know when to use each. A common trap is using a fillet where a chamfer is required, or forgetting that shell removes faces.
Work Features and Parameters
Work planes, axes, and points are essential for placing features. Parameters (user and model) drive dimensions; use them for design intent. Trap: mixing model parameters and user parameters incorrectly.
Rule of Thumb
Model with symmetry and patterns to reduce feature count. For a bracket with four identical holes, use a rectangular pattern rather than four separate hole features. This improves performance and editability.
Worked Example
Create a base plate 100×60×10 mm. Sketch a 100×60 rectangle, extrude 10 mm. Add four holes Ø8 mm at corners with 10 mm edge offset. Use a sketch on the top face, place a point, dimension it 10 mm from two edges, then use a rectangular pattern (2×2) with spacing 80 mm and 40 mm. Fully constrain all sketches.